The 20th century brought around the German catastrophe. After World War I, the use of German was suppressed and discouraged due to the anti-German sentiment, but nevertheless it did not inflict any lasting damage to its Sprachraum nor its lingua franca status in some areas. However, after World War II, territorial changes implemented by the Allies practically removed the German language from large parts of Central and Eastern Europe that were inhabited by German-speaking populations beginning in the 12th century. It contributed to moribundness and extinction of some local dialects like Silesian German, High Prussian or East Pomeranian dialects. Furthermore, it also damaged the language's status in Central-Western and Central-Southern Europe, where anti-German sentiment became even greater than before the war.

Middle High German

Middle High German (MHG, German Mittelhochdeutsch) is the term used for the period in the history of the German language between 1050 and 1350. It is preceded by Old High German and followed by Early New High German. In some older scholarship, the term covers a longer period, going up to 1500.

Early New High German

When Martin Luther translated the Bible (the New Testament in 1522 and the Old Testament, published in parts and completed in 1534) he based his translation mainly on this already developed language, which was the most widely understood language at this time. This language was based on Eastern Upper and Eastern Central German dialects and preserved much of the grammatical system of Middle High German (unlike the spoken German dialects in Central and Upper Germany that at that time had already begun to lose the genitive case and the preterite). In the beginning, copies of the Bible had a long list for each region, which translated words unknown in the region into the regional dialect. Roman Catholics rejected Luther's translation at first and tried to create their own Catholic standard (gemeines Deutsch) — which, however, differed from 'Protestant German' only in some minor details. It took until the middle of the 18th century to create a standard that was widely accepted, thus ending the period of Early New High German.

Low German was strongly influenced by Anglo-Frisian in Early Medieval times, and by High German during the duration of the Holy Roman Empire. After the end of the Hanseatic League in the 17th century, Low German was marginalized to the status of local dialects.

19th century

German was the language of commerce and government in the Habsburg Empire, which encompassed a large area of Central and Eastern Europe. Until the mid-19th century it was essentially the language of townspeople throughout most of the Empire. It indicated that the speaker was a merchant, an urbanite, not his nationality. Some cities, such as Budapest (Buda, German: Ofen), were gradually Germanized in the years after their incorporation into the Habsburg domain. Others, such as Bratislava (German: Pressburg), were originally settled during the Habsburg period and were primarily German at that time. A few cities such as Milan (German: Mailand) remained primarily non-German. However, most cities were primarily German at least during the early part of the century, such as Prague, Budapest, Bratislava, Zagreb (German: Agram), and Ljubljana (German: Laibach), though they were surrounded by territory where other languages were spoken.

Until about 1800, standard German was almost solely a written language. At this time, people in urban northern Germany, who spoke dialects very different from Standard German, learnt it almost as a foreign language and tried to pronounce it as close to the spelling as possible. Prescriptive pronunciation guides of that time considered northern German pronunciation to be the standard. However, the actual pronunciation of standard German varied from region to region.

Media and written works are almost all produced in standard German (often called Hochdeutsch in German), which is understood in all German-speaking areas (except by pre-school children in areas where only dialect is spoken, for example Switzerland — but in this age of television, even they now usually learn to understand Standard German before school age).

The first dictionary of the Brothers Grimm, which was issued in 16 parts between 1852 and 1860, remains the most comprehensive guide to the lexicon of the German language.

20th century

In 1880, grammatical and orthographic rules first appeared in the Duden Handbook. In 1901, this was declared the standard definition of the German language. Standard German orthography subsequently went essentially unrevised until 1998, when the German spelling reform of 1996 was officially promulgated by government representatives of Germany, Austria, Liechtenstein, and Switzerland. After the reform, German spelling underwent an eight-year transitional period, during which the reformed spelling was taught in most schools, while traditional and reformed spelling co-existed in the media.